The Duchess review

Keira wears it well in a formula frock opera

In case it had escaped your attention, Keira Knightley wears a corset well. She also looks mighty fetching in a powdered wig and is good at peering beguilingly from below the brim of a bonnet. Which is pretty much all she’s required to do in this beautiful but bloodless fashion show charting the tangled love life of 18th Century aristo Georgiana, the Duchess of Devonshire.

As a pretty 17-year-old married off to the Duke (Ralph Fiennes), Georgiana displeases her hubby by not immediately producing an heir; she then has a fling with ambitious politician Charles Grey (Dominic Cooper) when Devonshire moves his lover into their family pile, ménage-a trois style. Cue Keira bathed in candlelight; wearing a series of stunning syrups and frocks; click-clacking down magnificent marble hallways; pouting while staring into the middle distance; and gliding prettily through opulently dressed rooms as she languidly sips a claret. All very lovely. And predictable.

Director Saul Dibb may well have made the exhilarating Bullet Boy, but here he doesn’t stray from the prescriptive camera angles, lighting and set pieces of your average Sunday-night TV bodice-buster. And though Georgiana’s marital story and celebrity is clumsily made to mirror that of her descendant Princess Diana (the movie’s spell-it-out tagline? ‘There were three of them in her marriage’), the main event here is frock porn. Georgiana is brusquely de-flowered by her new hubby but isn’t her dress gorgeous? There’s glib mention of the French revolution, but look at the size of that hat. She’s about to cheat with Grey and isn’t that velvet cloak fabulous?

It’s easy to be distracted by the details thanks to damp chemistry between Cooper (failing to disguise his cor blimeys) and Miss K. Without the simmer Keira managed to generate with her leading men in Pride & Prejudice and Atonement, it’s hard to root for the duchess’ lust or empathise with her heartbreak. It’s left to Fiennes in sarcastic bastard mode to generate interest and spur Knightley into a couple of meatier acting moments.